The present invention relates to an ion storage device, a mass spectrometer, a method of storing ions and a method of mass spectrometry. The preferred embodiment relates to an ion storage device coupled between an ion mobility spectrometer or separator which operates over a first cycle time (e.g. 10 ms) and a second device such as a quadrupole mass filter or mass analyser which operates over a second slower cycle time (e.g. 100 ms).
It is known to couple an ion mobility spectrometer which typically operates over a cycle time of e.g. 10 ms to a Time of Flight mass analyser which typically operates over a faster cycle time of e.g. 100 μs. The ability to couple an ion mobility spectrometer to a faster Time of Flight mass analyser is due to the inherently fast analysis time offered by Time of Flight mass spectrometers which can, for example, acquire a complete mass spectrum very quickly e.g. in a timescale of 100 μs.
As a result, nested ion mobility spectrometry-Time of Flight acquisitions can be performed without loss of performance of either the ion mobility spectrometer or the Time of Flight mass spectrometer.
The coupling of an ion mobility spectrometer to a Time of Flight mass analyser has proven to be a powerful technique.
However, it is problematic to attempt to couple an ion mobility spectrometer or separator to other devices which operate on much slower time scales than Time of Flight mass spectrometers and ion mobility spectrometers or separators. For example, Fourier Transform mass spectrometers such as FT-ICR and electrostatic mass spectrometers, mass filters such as quadrupoles, ion traps and fragmentation devices such as Electron Transfer Dissociation (“ETD”) fragmentation devices, Electron Capture Dissociation (“ECD”) fragmentation devices and Proton Transfer Reaction (“PTR”) devices are comparatively slow and operate over a longer cycle time than conventional ion mobility spectrometers.
As an example, Electron Transfer Dissociation fragmentation devices, Electron Capture Dissociation fragmentation device and Proton Transfer Reaction devices typically operate over a timescale >100 ms and hence the separation of ions by an ion mobility separator over a timescale of 10 ms is too fast for such devices.
It will be apparent, therefore, that it is problematic to attempt to couple an ion mobility spectrometer or separator to certain other devices such as Fourier Transform mass spectrometers, quadrupoles, ion traps and fragmentation devices.
GB-2441198 (Franzen) discloses an ion storage bank comprising an array of RF multipoles arranged in parallel.
It is desired to provide an improved mass spectrometer and method of mass spectrometry.